以漂白针叶木浆为纤维原料,在2,2,6,6-四甲基哌啶氧自由基(TEMPO)-NaClO-NaBr的氧化体系下制备得到氧化纤维素纳米纤维.采用透射电子显微镜(TEM)、扫描电子显微镜(SEM)、红外光谱(FT-IR)、X-射线衍射仪(XRD)、热重分析仪(TG)等手段对氧化纤维素进行表征,并测定氧化纤维素羧基质量摩尔浓度.结果表明:该反应体系可以制得氧化纤维素纳米纤维.使用1 g纤维原料,在反应温度0～5℃、pH值10、NaClO用量3.0 mL、TEMPO用量0.016 g、NaBr用量0.100 g条件下,制得的纳米纤维的羧基质量摩尔浓度达0.67 mmol·g-1,而且氧化制得的纳米纤维的沉降性能也显著提高.%Bleached softwood kraft pulps were oxidized by 2,2,6,6-tetramethylpiperidine-oxyl radical (TEMPO) -NaC10-NaBr oxidation system. The obtained oxidized cellulose was characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM) , infrared spectroscopy (FT-IR), x-ray diffraction (XRD) , and thermogravimetric analysis ( TG), and the molality of carboxylate was measured. Results show that the cellulose nanofibers can be obtained by the oxidation system. The optimal conditions for the oxidation reaction of 1 g raw cellulose fibers were obtained as NaClO 3.0 mL, TEMPO 0.016 g, NaBr 0. 100 g, reaction temperature 0-5 degrees C, and pH 10. The carboxylate molality of resultant TEMPO-oxidized cellulose reached 0.67 mmol· g-1. Moreover, the deposition properties of the oxidized nanofibers were improved significantly.
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